Here's a bit of trivia that may help when estimating your range. Energy consumed goes up by the square of the speed. Thus a car traveling 70 mph uses four times the energy of one traveling at 35 mph. For other circumstances, let's say the difference between traveling at 60 mph versus 70 mph, 70 squared equals 4,900 and 60 squared equals 3,600. Divide 4,900 by 3,600 and the answer is 1.36 or 36% more energy. For only 10 mph difference the extra energy consumed is considerable. The difference between 55 and 75 is 86% more energy required which is even more sobering.